ABSTRACT
CONTEXT AND OBJECTIVE Oxaliplatin is one of the chemotherapy regimens most used for treating colorectal cancer. One of the main limitations to its use is induction of peripheral neuropathy. Previous studies have shown that vitamin E can reduce the incidence of peripheral neuropathy by 50%. This study aimed to assess the effectiveness of vitamin E for prevention of oxaliplatin-induced peripheral neuropathy. DESIGN AND SETTING Prospective, phase II, randomized pilot study developed at a university hospital in the Greater ABC region. METHODS Patients were randomized five days before starting oxaliplatin treatment, to receive either vitamin E or placebo until the end of the chemotherapy regimen. The outcome was evaluated using the Common Terminology Criteria for Adverse Events (CTCAE), version 3, and specific gradation scales for oxaliplatin-induced peripheral neuropathy. Patients with colorectal and gastric cancer who had been scheduled to receive oxaliplatin-based chemotherapy were included. Both groups received calcium and magnesium supplementation before and after oxaliplatin infusions. RESULTS Eighteen patients were randomized to the vitamin E group and 16 to the placebo group. Cumulative incidence of 83% with peripheral neuropathy grades 1/2 was observed in the vitamin E group, versus 68% in the placebo group (P = 0.45). A trend towards more diarrhea was observed among patients who received vitamin E (55.6% vs. 18.8%; P = 0.06). There were no other significant differences in toxicity between the groups. CONCLUSIONS No significant decrease in the incidence of acute oxaliplatin-induced peripheral neuropathy was demonstrated through vitamin E use.
Subject(s)
Antineoplastic Agents/adverse effects , Colorectal Neoplasms/drug therapy , Organoplatinum Compounds/adverse effects , Peripheral Nervous System Diseases/prevention & control , Vitamin E/therapeutic use , Vitamins/therapeutic use , Adult , Aged , Female , Humans , Male , Middle Aged , Oxaliplatin , Peripheral Nervous System Diseases/chemically induced , Pilot Projects , Prospective StudiesABSTRACT
Oxaliplatin is one of the chemotherapy regimens most used for treating colorectal cancer. One of the main limitations to its use is induction of peripheral neuropathy. Previous studies have shown that vitamin E can reduce the incidence of peripheral neuropathy by 50%. This study aimed to assess the effectiveness of vitamin E for prevention of oxaliplatin-induced peripheral neuropathy. Prospective, phase II, randomized pilot study developed at a university hospital in the Greater ABC region. Patients were randomized five days before starting oxaliplatin treatment, to receive either vitamin E or placebo until the end of the chemotherapy regimen. The outcome was evaluated using the Common Terminology Criteria for Adverse Events (CTCAE), version 3, and specific gradation scales for oxaliplatin-induced peripheral neuropathy. Patients with colorectal and gastric cancer who had been scheduled to receive oxaliplatin-based chemotherapy were included. Both groups received calcium and magnesium supplementation before and after oxaliplatin infusions. Eighteen patients were randomized to the vitamin E group and 16 to the placebo group. Cumulative incidence of 83% with peripheral neuropathy grades 1/2 was observed in the vitamin E group, versus 68% in the placebo group (P = 0.45). A trend towards more diarrhea was observed among patients who received vitamin E (55.6% vs. 18.8%; P = 0.06). There were no other significant differences in toxicity between the groups. No significant decrease in the incidence of acute oxaliplatin-induced peripheral neuropathy was demonstrated through vitamin E use. A oxaliplatina é um dos quimioterápicos mais utilizados no tratamento do câncer colorretal, sendo a indução da neuropatia periférica (NP) uma das principais limitações para o seu uso. Trabalhos anteriores demonstraram que a vitamina E poderia reduzir a incidência dessa neuropatia em 50%. Este estudo teve como objetivo avaliar a efetividade da vitamina E na prevenção da NP induzida pela oxaliplatina. Estudo piloto prospectivo e randomizado de fase II desenvolvido em hospital universitário do Grande ABC. Os pacientes foram randomizados para receber vitamina E ou placebo por cinco dias antes do início do tratamento com oxaliplatina e até o término do regime quimioterápico. O desfecho foi avaliado através dos Critérios Comuns de Toxicidade do Câncer versão 3 (CTCAE) e escalas específicas de gradação da NP induzida por oxaliplatina. Foram incluídos pacientes com câncer colorretal e gástrico programado para receber quimioterapia baseada em oxaliplatina. Ambos os grupos receberam suplementação de cálcio e magnésio antes e depois das infusões de oxaliplatina. Dezoito pacientes foram randomizados para grupo da vitamina E e 16 para o grupo placebo. Observou-se incidência cumulativa de 83% das classes I/II de neuropatia periférica no grupo da vitamina E, contra 68% no grupo placebo (P = 0,45). Observou-se maior tendência à diarreia em pacientes que receberam vitamina E (55,6% versus 18,8%, P = 0,06). Não houve outras diferenças significativas quanto às toxicidades entre os grupos. ...Subject(s)
Adult
, Aged
, Female
, Humans
, Male
, Middle Aged
, Antineoplastic Agents/adverse effects
, Colorectal Neoplasms/drug therapy
, Organoplatinum Compounds/adverse effects
, Peripheral Nervous System Diseases/prevention & control
, Vitamin E/therapeutic use
, Vitamins/therapeutic use
, Peripheral Nervous System Diseases/chemically induced
, Pilot Projects
, Prospective Studies
ABSTRACT
Peptidoglycan (PEG) and lipoteichoic acid (LTA) are the main constituents of Gram-positive bacteria cell wall and are described to modulate immune functions. Increased levels of matrix metalloproteinases (MMPs) were described in endotoxemia, suggesting that they participate to tecidual damage, multiple organs failure and vascular disfunction. Staphylococcus aureus PEG is described to increase MMPs 2 and 9 levels in plasma from rat and MMP 9 secretion by human neutrophils, however, the effect of LTA on MMPs is unknown. In this work, was evaluated the modulation of MMPs 2 and 9 expression and secretion in RAW 264.7 macrophages by LTA from S. aureus. The role of A2A and A2B adenosine receptors was also investigated. LTA increased MMP 9 expression and secretion at 12h of treatment. The modulation of MMP 9 secretion was dose dependent, with maximal effect above 1microg/ml. The inhibitor of mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway (U0126, 10microM) prevented LTA stimulation of MMP 9 secretion; however, the inhibitors of p38 (SB203580, 10microM) and Jun N-terminal kinase (JNK; SP600125, 10microM) presented any effect. A2A and A2B adenosine receptors pharmacological blockade or gene knockdown resulted in exacerbated MMP 9 secretion, while an adenosine receptors agonist inhibited LTA-stimulated MMP 9 secretion. These results suggest that LTA increased MMP 9 secretion in macrophages could be involved in complications associated to S. aureus infections. Moreover, LTA modulation of MMP 9 is dependent on MEK/ERK pathway and is regulated by A2A and A2B adenosine receptors.
